Electrolytic process of treating alkaline compounds.



E. e. EKSTROM.

ELECTROLYTIC PROCESS OF TREATING ALKALINE COMPOUNDS.

APPLICATION FILED DEC. 7, 1910.

1,003,041 Patented Sept." 12, 1911.

Inventor. witnesses.

I I Z'rzzet illwarom, W

UNITED STATES.

PATENT OFFICE.

ERNST G EKSTROM, 01, LOS ANGELES, CALIFORNIA.

nmacrnonrrrc rnqfciiss orji ranarmc ALKALINE 'cotrroumis.

Specification ct Letters Iatent. Patented Sept. 12

Application filed December 7, 1910. Serial No. 596,612..

To all whom it may concern:

Be it known that I, Emwsr G. EKsTRoM, a citizen of Sweden, residing at Los Angeles,

county of Los Angeles, State oi California,

have invented new and useful Improvements in Electrolytic Processes of Treatin Alk'achlorin gases are liberated .in large qua'ntities and'partiall allowed to escapeinto the atmosphere,,ma 1.n g it very dangerous and destructive to life and-material, an economical loss in-this .way being inevitable.

process. I of manufacturing alkaline-hydroxids electrolytically from. their salts without liberating an suffocating gases, but instead obtaining valuable acids as 1 byproducts.

In order to set forth the process I give as an example my rocess applied in the manudium chlorid, as follows:

Method A.--First, the preparation of.the"

electrolyte: The sodium chlorid is dissolved in water to form a solution, which is treated in a wooden tub or similar vessel, with a predetermined quantity of hydrofluosilicicacid, H SiF In treating the salt with this acid a white sediment of sodium-fluosilicate,-

Na,SiF is precipitated, separating a solution of hydrochloric acid, H01. The reaction which takes place is as follows:

The solution of hydrochloric acid is decanted from the precipitate and is collected in a special tank, The white sediment or. precipitate remaining in the tub is washed; with water in order to eliminate every possi ble trace of chlorin inthe state of hydro chloric acid or sodium chlorid, (excess). To the sediment or precipitate, Na,SiF,,, an

aqueous solution of hydrofluosilicic acid is added, bringing part of the sediment into solution and forming an'electrolyte.

Second, the electrol sis: Having produced an electrolytein the manner described above, I introduce a quantity of the same in a suitable vessel in which a porous diaphragm is inserted dividing the cell into two compartments, and in each of these compartments a oxid by using so-" graphite-electrode is suspended on copper conducting strips. One'of these electrodes forms an anode and the other one a cathode, when t e electric current is sent through the anode compartment, I introduce an excess of saturated with this salt. After having acidified or alkalified the water of the cathode compartment, '1 in order to increase ready for electrolysis; When the circuit is closed the electrolytebecomes decomposed into its ions, sodium,*Na,-, being cation and fluosilicon, SiF being an ion, the-two of which are migrating-to the cathode and- The object ofthis invention is to provide aanode respectively. This decomposition is two ions are set free 'at the electrodes, :1 secwill immediately take place, that is, in practice it occurs simultaneously with the liberation of. the two ions; In the cathode compartment, thus, the-'sodiumeion' exerts chemical action upon the 'waterforming sodium ating hydrogen, H, and in the anode comoxygen, 0. These two. reactions take place in accordance with the followingch'emical equation:

Electrolyte (partially dissociated), y Anode. Cathode. Primary reaction (bg' electrolysis) SiFi Na: Secondaryreaction iFfl-HzOeeHzSiFq-I-O; Nari-2H,):

' 1' 2NaOH-l-Hg In this wayI produce caustic soda as a catholyte and bring about a regeneration of hydrofluosilicic a01dj10m the anolyte .enabling both of these substances to be drawn ofl' separately, the alkali to be concentrated and the acid to be used for making new electrolyte. v If it is desired to facilitate the reactions just given above, compressed air may be in ected in order to bring the liquid in good circulation during t e process. Steam injection is alsq favorable as the solubility of the sodiumfluosilicate will be considerably increased by the higher temperature caused by the steam.

Third, the concentration of the lye of caustic soda: The caustic soda produced as indicated above, may then be concentrated solution. In the electrolyte which is in the the primary reaction'which is a dlrect conse-. quence of the electrolysis. 'As soon as these ondary reaction with the surrounding water hydroxid, NaOH, that is caustic soda, libe'rsodium fluosilicate, still'undiss'olved and in this way I keep the electrolyte continually its electric conductivity,=the apparatus is partment, the fluosilicon-ion SiF is con- 'verted into hydrofluosilic acid, liberating 

